Guardrail testing

[tayloraiape]

When testing a balcony guardrail for the code required point loading, does the post need to resist a 200# load or does it need to resist 200x1.6= 320#? When performing the load test, the question is whether you add a safety factor to the 200# load? This is an in-place guardrail where we are trying to determine if the connection to the balcony facade meets the code requirement. Is it 200# or 320# that needs to be placed against the post by the testing apparatus? I am not concerned about the post or railing themselves, only the connection at the bottom of the post to the balcony facade. It is wood framing and the testing company is saying the load they need to apply is 320# without a specific deflection. Any help would be appreciated.

 

[JAE]

Assuming you are under the IBC - look at IBC section 1709. SF = 2.0. For guardrails there are no deflection requirements listed in section 1604.3.

 

[tayloraiape]

We are using the 2012 IBC. Are you saying the guardrail should resist 400# (200x2)to be considered in compliance with the IBC?
If so, it appears the IBC is very unclear on this.

 

[JAE]

The IBC Commentary and ASCE 7 both state 200 lbs. concentrated load or a 50 plf load along the top rail in any direction.

If you, as an engineer, can calculate and design the guard - and its attachments - all through the full load path, then no testing is required.
The design would follow all code provisions which require either allowable stress design or LRFD with their associated safety/load factors.

If you can't design it because:
1. It is a weird, or unique, system, or
2. It is existing and the material, design and construction information isn't complete enough for you to check its capacity...

then you need to perform a load test per the IBC section 1709 above...with a test load of 2 x 200 lbs.